Is that Jim Halpert from The Office?

John Krasinski looks jacked in new photos for Men's Health magazine. The 36-year-old actor flaunted his ripped body for the publication, posing in a muscle-baring tank top.

Krasinski buffed up for his role as a Navy SEAL in 13 Hours: The Secret Soldiers of Benghazi and enlisted personal trainer, Jason Walsh, to help him get in fighting shape. "Getting stronger every day is thrilling," he said of the workout and diet plan.

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Emily Blunt's husband did admit that his body transformation wasn't easy. "I gotta be honest: It was brutal at times," Krasinski said. "We did tons of metabolic work, dragging sleds and all this stuff I've seen NFL players do."

The former NBC star also revealed the best and worst parts of his workout, starting with his favorite song to exercise to, Jay Z's "What More Can I Say." He's also a big fan of the bench press. "There's that number you can keep pushing," he said. "It's almost a game instead of a workout."

Krasinski, however, isn't so keen on the Bulgarian split squat. This is when you stand in a lunge position with your foot on top of a workout bench and squat as you hold dumbbells in each hand. Ouch!

WATCH: Chris Pratt Wants to Drop 20 More Pounds, But Warns He'll 'Go Back to Being the Fat Guy'

Another NBC actor that got super buff for the big screen is former Parks and Recreation star Chris Pratt. "I'd gone back and forth, lost weight for Moneyball, got fat again, then trimmed down for Zero Dark Thirty, then gained it all back again for Andy," Pratt recalled to Men's Health UK. "That's when I saw Zero Dark Thirty and right after walking out I was like: 'I'm going to get in shape and I'm never going to be fat again.'"

The Jurassic World star also revealed that before his weight loss, he was impotent and "emotionally depressed." Here's more from Pratt about his transformation:

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